1. Field of the Disclosure
This disclosure generally relates to a touch device and, more particularly, to a capacitive sensing device capable of suppressing the influence from the mutual capacitance in a self-capacitance mode.
2. Description of the Related Art
As a touch panel can be operated instinctively by a user, it is widely applied to various electronic devices. Touch panels are generally divided into capacitive, resistive and optical touch panels.
The capacitive touch sensor can further be divided into the self-capacitive touch sensor and the mutual capacitive touch sensor. These two types of touch sensors have different characteristics of capacitance variation to be adaptable to different applications. For example, the mutual capacitive touch sensor may be configured to perform the multi-touch detection, whereas the self-capacitive touch sensor has a higher sensitivity to the hovering operation and a lower sensitivity to water drops.
For improving the usability, some capacitive sensing devices may be operated in a self-capacitance mode and a mutual capacitance mode for different scenarios or applications, respectively. However, the operation in the self-capacitance mode can be easily influenced by the mutual capacitance to lose the high sensitivity to the hovering operation or the low sensitivity to water drops.